Remove dependencies nothing imports and stale RSS .gitignore entries

None of these packages are imported by src/, dev/, or any config file:
@docsearch/react (only its CSS is vendored), @mdx-js/mdx, date-fns,
fast-glob, feed, prism-react-renderer, react-highlight-words and its
@types, react-syntax-highlighter, rehype-toc, simple-functional-loader,
dotenv.

public/changelog.rss and public/technical-changelog.rss are no longer
generated here: the feed is served from sourcegraph.com (see
src/data/constants.ts) and src/proxy.ts redirects to it.

Amp-Thread-ID: https://ampcode.com/threads/T-01a0ad56-bd79-73ce-bc8e-a5405d0c11f2
Co-authored-by: Amp <amp@ampcode.com>

Author: marcleblanc2

.gitignore

@@ -43,16 +43,11 @@ next-env.d.ts
 # IDEs
 .idea
 
-# We ignore the generated file as it should always be generated
-public/changelog.rss
-
 # env file
 .env
 
 # amp orb portal state
 .amp/portals/
 
-public/technical-changelog.rss
-
 # script output
 logs/

package.json

@@ -27,47 +27,36 @@
 	"dependencies": {
 		"@algolia/autocomplete-core": "^1.13.0",
 		"@algolia/client-search": "^4.22.1",
-		"@docsearch/react": "^3.5.2",
 		"@headlessui/react": "^2.2.10",
 		"@heroicons/react": "^2.1.1",
 		"@iconify-json/logos": "^1.2.10",
 		"@iconify/types": "^2.0.0",
-		"@mdx-js/mdx": "^3.1.0",
 		"@radix-ui/react-hover-card": "^1.1.5",
 		"@radix-ui/react-select": "^2.0.0",
 		"@radix-ui/react-slot": "^1.0.2",
 		"@tailwindcss/typography": "^0.5.10",
 		"@types/node": "24.13.4",
 		"@types/react": "19.3.0",
 		"@types/react-dom": "19.3.0",
-		"@types/react-highlight-words": "^0.16.7",
 		"algoliasearch": "^4.22.1",
 		"autoprefixer": "^10.4.16",
 		"class-variance-authority": "^0.7.0",
 		"clsx": "^1.2.1",
 		"contentlayer2": "^0.5.8",
-		"date-fns": "^2.30.0",
-		"fast-glob": "^3.3.2",
-		"feed": "^4.2.2",
 		"github-slugger": "^2.0.0",
 		"lucide-react": "^0.372.0",
 		"mdx": "^0.3.1",
 		"mermaid": "^11.16.1",
 		"next": "^16.3.5",
 		"next-contentlayer2": "^0.5.8",
 		"next-themes": "^0.4.6",
-		"prism-react-renderer": "^2.3.1",
 		"react": "19.3.0",
 		"react-dom": "19.3.0",
-		"react-highlight-words": "^0.20.0",
-		"react-syntax-highlighter": "^15.6.1",
 		"rehype-autolink-headings": "^7.1.0",
 		"rehype-pretty-code": "^0.10.2",
 		"rehype-slug": "^6.0.0",
-		"rehype-toc": "^3.0.2",
 		"remark-gfm": "^4.0.1",
 		"shiki": "^0.14.7",
-		"simple-functional-loader": "^1.2.1",
 		"svg-pan-zoom": "^3.6.2",
 		"tailwind-merge": "^2.3.0",
 		"tailwindcss": "^3.4.0",
@@ -76,7 +65,6 @@
 		"unist-util-visit": "^5.0.0"
 	},
 	"devDependencies": {
-		"dotenv": "^16.4.7",
 		"eslint": "^9.39.5",
 		"eslint-config-next": "16.3.5",
 		"glob": "^11.0.3",